Two-cycle opposed-piston diesel engine



April l, 1941.-- F. w.- PLUME CYCLE OPPOSED-PISTON DIESEL ENGINE Filed March 13, 1959 2 Sheets-Sheet l M 2 wv 4 m w 7 m6 2 0 m7, M 0o7. 740

v Smoentor:

April 1', 19417 F. w. PLUME TWO-CYCLE OPPOSED-PISTON DIESEL ENGINE Filed liarch 13. 1939 6.x 1a 2f 10 70 Patented Apr. l, 1941 OFFICE TWO-CYCLE OPPSED-PISTON DIESEL ENGINE Frederic W. Plumb, West Reading, Pa. Appli-,ation Maren 1s, 1939, serial No. 261,447'

l 8 Claims.

My inventionrelates to internal combustion engines commonly known `as Diesel engines, 'and more particularly to a known type of the same employing opposed pistons in a single cylinder operating on a two-cycle stroke; my main objects being to produce an engine of improved design, inherently balanced, of increased eiliciency, economical operation, and of simple inexpensively manufactured units of interchangeable parts suitable for mass production and multiple assembly into power units of varying capacity.

It is recognized and accepted that better results in eiliciency and economy of fuel consumption are obtained by use of a two cycle `stroke with opposed pistons in one cylinder giving a comparatively longer time for power expansion,

and preferably in connection with water-cooled cylinders cast separately, instead of in a block of multiple cylinders; and it is an important object of my .present invention to embody these desirable features in a novel and improved combined cylinder-and-crank-case unit, which may be used singly, or assembled with added like units, into an engine of any desired multiple cylinders, differing from any engine heretofore known to me, and providing for true economical mass production of varyingly powered engines of great simplicity and increased eiliciency.

Other important objects of my invention relate to a differential action of the opposed pistons causing them to operate as valves in the control of both inlet and exhaust posts; to a Vsimplification in the linkage of the pistons to the crank shaft and arrangement of the same to act in a single plane passing through the axis of the cylinder so as to materially reduce strains and wear on these working parts; to a unique type of mixing chamber and fuel injection nozzle of larger size than usually needed, providing for a violent state of turbulence in the cylindercompressed air and injection of fuel charges at a lower rate of compression, to insure proper combustion; to a novel crank case compression of air acting in simple manner, without added blower or supercharger to eifectively scavenger the burnt gases of combustion and supply new air for compression of the cylinders; to a novel construction of the cylinder case with an integral water jacket and fixed inlet and exhaust ports partly encircling the cylinder and with their openings into the latter inclined at angles to thev cylinder axis so as tovreduce friction and wear: and to the use of tubular bolts for uniting end housings, and/or a plurality of combined cylinder-and-crank-.ca se units on a suitable multiple cranked-shaft. said tubularbolts also acting to convey lubricating oil to and from the crank cases.

With the above objects outlined, and with other objects that will later hereinafter appear, my invention comprises the new and improved engine construction more fully described in the following specification in connection with the Adrawings accompanying the saine, and its novel features are particularly set forth in the appended claims. In the drawings:

Fig. 1 is mainly a vertical sectional elevation of a cylinder-and-crank-case unit'showing a preferred embodiment of my invention, the view being taken substantially on the line I-l of Fig. 2 in a plane passing through the axis of the cylinder, with one end closure for the cylinder case shown in section and the other ln side elevation, and an added fly-wheel housing being indicated.

Fig. 2 is a transverse view taken on the line 2-2 of Fig. 1, showing the crank case in vertical cross-section, and an open end view of the cylinder case with the separate end closure thereior removed, and also indicating in, cross-section a fly-wheel housing and a pump gear-case housing secured to the crank shaft; dotted lines further indicating the position of an added unit ln piace of the fly-wheel housing.

Fig. 3 is a. plan view corresponding with Fig. 1, but shown partly in section in the plane ofthe cylinder axis, taken on the line 3 3 of Fig. l.

, Fig. 4 is a'detail section, taken on the line 4-4 of Fig. 2, indicating the manner of connecting my unit to an end housing or an added like unit.

Figs.5 and 6 -show respectively a side and plan view ofv a, link employed in triplicate in connecting the cylinders to the crank shaft, as seen in Fig. 1.

Figs. '7, 8 and 9 show three transverse crosssectional views of the cylinder chamber ,and its surrounding jacket, being taken respectively on the lines 1 1, 8-8, and 9--9 of Fig. 1, and indicating in order the exhaust port, the mixing chamber and fuel oil injector nozzle, and the air inlet port.

Figs. 10 to 13 are diagrammatic sectional ele-4 vations corresponding with Fig. 1, indicatingthe cycle of piston actions: FigflO showing the beginning of a power stroke; Fig. 11, the scavenging of the burnt gases; Fig. 12 the vintake of fresh air; and Fig. 13 the air-compressing movement of the pistons. v

Fig. 141s a side elevation indicating an outside view of three units fixedly united according to my invention to form amulti-cylinder engine.

In accordance with my invention each cylinder and crank case forms a separate engine unit and is designed for manufacture in single units to facilitate mass production and multiple assembly. For convenience and economy, and the use of a diversity of materials best adapted for particular needs, each unit is made up of separate interchangeable parts, 5 in the drawings indicating the open-ended cylinder case having similar separate end-closures 6 and 1, and a colinected crank shaft casing preferably formed in complementary parts 9 and I0 connected in the midway plane of their shaft bearing bosses II and 'I2 in halves. The case 5 is formed with a crank case 4extension chamber I5 and a cylinder chamber I6 having a surrounding water jacket chamber II interrupted midway of its length for a mixing fuel injection passage-way (Fig. 8), and spaced half encircling exhaust chamber 2| (Fig. 7), and opposite half-encircling inlet chamber 24 (Fig. 9). Chamber 2| has ports 22 communicating with cylinder chamber I6 and an outlet 23 adapted for connection to an exhaust manifold not shown. Chamber 24 has ports 25 communicatingwith cylinder chamber I6, and a passage-way 26 communicating with crank case extension chamber I5. Water jacket chamber I'I has inlet and outlet passage-ways I8 and I9 respectively for connection to a water cooling circulating system not shown. Ports 22 and 25 are preferably inclined to the axis of the cylinder chamber to reduce friction and wear.

Opposedly acting pistons 30 and 40 are fitted to slide longitudinally in open-ended cylinder chamber I6, and jointly act on a single crank pin 45 having a' single connecting rod 46, through suitable linkage including similar rock levers 3l and 4I pivotaliy mounted intermediate their length at 32 and 42 respectively in suitable bearings provided in cylinder case 5, as shown, and three similar links (Figs. 5 and 6). Lever 4I has one end pivotally connected at 43 directly to the free end of connecting rod 46, and its other end pivotally connected to piston 40 through a link 44. Arm 3I has one end pivotally connected `to piston 30 through link 34 and its other end pivotally connected by a link 35 to a pivotal connectiton 36 located midway the length of connecting arm 46.

This particular linkage connection of the pistons 30 and 40 to the single crank pin 45, has manifold advantages, of economically using numbers of quantity-producible like parts, acting as effectively as if there were two instead of one connecting rod, providing for large pivotal connections readily equipped with effective antifriction bearings, producing a differential action of the pistons for a purpose later herein described, causing all stress and strain to act in an inherently balanced and powerfully effective straight line due to the linkage alinement in a plane, and even and uniform surface Wear on pistons and cylinder walls, insuring their long service tight fitting.

The crank case and cylinder passages, as shown, are comparatively small and effectively lend themselves to practical crank case compression, thus avoiding any need of blower or supercharger for scavenging; air being drawn into said passage through ports 48 controlled by plate valves 49 (Figs. 1 and 2), formed in the top wall of each cylinder case end-closure 6 and 1, and the compressed air passing through passage-way 26 into chamber 24 and through ports 25 into the cylinder chamber I6. Conversely exhaust gases pass rthrough ports 22 into chamber 2| and thence through outlet 23.

Passage-way 20 (Fig. 8) is shown as tangential to the cylinder and connects the latter to a novel mixing chamber containing a sleeve nozzle 50 and a spiral director 5I, both preferably of a high heat resistant alloy metal, and fuel oil is injected through a check valve 53 to a spray nozzle 52, by a pipe connection to an injection pump, not shown, the action and timing of which may be controlled by driving connection with shaft-driven gears in housing 65 (Figs. 2 and 3). The air in cylinder I6 as compressed by pistons 3l! and 40 is raised to a high degree of temperature and forced into a violent state of turbulence by surging into the mixing chamber and by the action of nozzle 50 and spiral director 5I, and at its maximum state of compression a spray of fuel oil is injected to form a combustible mixture, as well understood in Diesel engine operation. This novel type of mixing chamber and its advantageous location midway in the water jacket I'I, enables me to use a larger nozzle bore than is usually considered necessary, and to inject the fuel spray charges at a lower compression ratio, saving power without loss in eiiiciency of the combustible mixture.

The linkage connection of crank pin 45 to pistons 30 and 40'before described has a differential action on said pistons permitting use of the saine for controlling the covering and uncovering of the inlet ports 25 and outlet ports 22 in timedV relation to their cycles of movement. Referring now particularly to Figs. 1 and 10, which show pistons 30 and 46 at the end of their compress ion strokes and the crank pin 45 at its lower dead center but moving in the direction of arrow 55, pivot 36, having a shorter radius than pivot 43, swings its link 35 from a dead center alinement with crank pin 45 to an angular inclination therewith, so that piston 30 connected to link 35 through rock lever 3| and link 34 take a lead'in its outward power stroke movement over piston 40, due to connecting arm 46 passing through its dead center alinement with the crank shaft axis which causes a dwell in movement of rock lever 4I connected by link 44 to piston 4l, This lead of piston 30 continues throughout the piston power stroke so that exhaust ports 22 are uncovered before inlet ports 25 are opened. Link 35 reaches its upper dead center alinement with crank pin 45 causing piston 30 to dwell while piston 40 continues its outward movement to open inlet ports 25. assumed the position shown in Fig. 11, and the incoming air acts to scavenger the exhaust gases. Connecting arm 46 again passes through its upper dead center alinement with crank shaft axis while link 35 again assumes an angular inclination with crank pin 45 so thatpiston 30 leads in itsinward compression stroke to close exhaust ports 22 while piston 40 dwells with ports 25 open,

admitting a charge of fresh air to cylinder I6..

as shown in Fig. 12. Fig. 13 shows both ports 22 and 25 closed and pistons 30 and 40 moving inward to their compressed position with piston 30 maintaining its lead, until they reach full compression position as shown in Figs. 1 and 10,

ready to receive a fuel oil injection for the next power stroke. Air is drawn'in through ports 46 in end closures 6 and 1 during each compression stroke of pistons 30 and 40 and passes into cylinder chamber I6 at the end of each power 'I'he moving parts have now fthrough the bosses 10, 10 and 52, 61.

stroke of said pistons. 'I'his timed opening and closing of the exhaust ports 22 in advance ofthe opening and closing of the inlet ports 25 with a joint period of both being opened to thoroughly scavenger the burnt gases, is 'simply and positively provided for by the above described differential action of pistons 30 and 40, which also act to compress the necessary fuel air in the crank case.

In Fig. 2 I have indicated an engine assembly according to my invention consisting of a single combined cylinder-and-crank-case unit having a ily-wheel housing '60 and a gear housing 65 connected thereto at opposite ends of the snglec cranked shaft 15 shown. My combined unit has parallel side face portions of a width corresponding with the end faces Aof shaft bearing bosses IL-l2 projecting from b oth sides of crank case parts 9 and I0, and the latter are provided with bolt bosses 10, 1li arranged in spaced circumferential relation, the end faces of which are also in alinement with the end faces of bosses li'-|2.

Fly wheel housing B and gear housing 55, which may be of split sections if desired, are each provided with shaft bearing bosses 6I and 56 complementary to bosses |II2 and arranged to abut against the latter end-to-end, also bolt bosses 52 and 51 arranged to aline with bosses 1l, 1l and engage against the same end-to-end. Parted clamping rings 58 or 69 are shown as xedly uniting the respectively bosses and Il-i2 and 66 and II-I2 (Fig. 4). And to firmly tie said housing B0 and 55 to the crank caseI 9-10, ibolts 1|, 1| are showin engaging In Fig. 2, dotted lines indicate a second combined cylinderand-crank case unit substituted for ily wheel casing 60 and united in the manner described for the latter, and any number of units may be connected together in similar manner and their end cries having housings 50 and 65 attached therethem in the crank case parts 9 and l0 and the sealing of the air and oil tight crank case may be secured by the use of sealing rings indicated at 18. The shaft is also shown with bearing collars 29 ttedwithin the bearing bosses 5I, II-I2 and 66, Ii-I2, preferably split atan angle of 180 to the split of said bearings.

To provide adequate lubricating oil to the crank case for simple splash distribution, the

bolts 1I, 1l are shown as formed of tubing and provided with apertures therefrom through their bosses 10, 10 leading into the crank case chamber; the upper bolt being used to furnish the oil supply, and the lower bolts to remove the used 4'-oil. End caps may be used to close said tubular bolts, and piping employed to connect them to a usual supply pump and a sump pump and filter, not shown, conveniently driven from the gears in housing 65. v

lassembly, a drive shaft having a plurality of i modiiied and changed within the scope of the following claims.

What I claim is:

1. A two-cycle opposed piston engine of the compression-ignition internal-combustion type, comprising a plurality of similar interchangeable' combined cylinder-and-crank-case complete engine units adapted for connected side-by-side assembly,'a drive shaft having a plurality of crank pins, one for each assembled engine unit, end housing units on said shaft connected to the respective end engine umts, and means for flxedly uniting said units so as to form lubricant passage-ways to the interiors of the latter. l

2. A two-cycle opposed piston engine of the compression-ignition internal-combustion type, comprising a plurality of similar interchangeable combined cylinder-and-crank-case complete engine units adapted for connected side-by-side crank pins. one for each assembled engine unit, and end housing units on said shaft connected to the respective end engine units, said units having parallel abutting wall portions, and hollow tiebolts fixedly uniting the same and forming lubricant passage-ways to the interiors of vthe latter. 3. A two-cycle opposed piston engine -of the compression-ignition internal-combustion type, comprising a plurality of similar interchangeable combined cylinder-and-crank-case complete engine units adapted forconnected side-by-side assembly, a drive shaft having a pluralityof crank pins, one for each assembled engineunit, and end housing umts on said shaft connected to the respective end engine units, said `shaft having concentric sealing discs on each side of each crank pin, and each engine unit having internal bearing recesses adapted to receive said discs, and oil-sealing rings in the periphery of each disc.

4. A two-cycle opposed piston engine of the compression-ignition internal-combustion type, comprising a plurality .of similar interchangeable combined cylinder-and-crank-case complete engine units adapted for connected side-by-side assembly, a drive shaft having a 'plurality of crank pins, one for each assembled engine unit, and end housing units on said shaft connected to the respective end engine units, each of said engine units having component parts of different metals forming a combined open-ended cylinder It is believed the nature ofmy invention and its manner of operation will. be readily understood from the foregoing description. It is of the simplest design, economical to manufacture, may be assembled into multiple units, occupies comparatively little spaceand may be made of unusual lightness for a Diesel engine, practically and crank case unit, and like end-closures for said unit having valved air-inlet ports and formtending into said air-chamber, a transversely mounted crank shaft in said casing having a single crank pin with an operating arm mounted thereon, and operating connections between each of said piston-pivoted links and said crank opery ating arm whereby the piston impulses are cooperatively transmitted to the crank shaft.

6. In a construction as set forth in claim 5, crank-operating connections to the oppositeiy moved pistons comprising similar xedly-pivoted rock-arms each linked at one end to the respective pistons and having their other ends swingingly connected to said crank-pin operating arm at differently located portions thereof relative to the center of the crank-pin so as to cooperatively rotate the latter substantially as described.

'7. In a construction as set forth in claim 5, a cylinder having hollow walls forming a water 

